Our goal is to increase the share of either recycled or renewable raw materials in tires to 50% by 2030, and we are actively looking for and testing renewable raw materials. Our aim is to find renewable raw materials for various raw material groups, create eco-friendlier tires, and replace fossil raw materials. We will also reduce the use of harmful substances, thereby improving occupational safety in production. We were the first in our industry to give up the use of high-aromatic oils.
The use of new raw materials requires a great deal of product development efforts and testing to find the best combination of properties for a tire, as new raw materials can modify the compound properties. In materials development, the use of renewable materials must not alter a tire’s safety characteristics. The choice of new materials can also be affected by the material not being fossil based, as that makes the material a more sustainable option.
Nokian Tyres was the first tire company to give up the use of harmful HA (high-aromatic) oils in production. The global research of oils and resins from renewable sources to replace the low PAH content oils is active, but their commercial availability is still limited in the tire industry. Nokian Tyres has an active role in this constantly evolving research and industrialization process. We are already using renewable oils such as rape seed oil and tall oil in our rubber compounds and we continue to research them. Our work to increase the renewable oil content in our rubber compounds is aligned with our goal
of increasing the share of renewable and recycled raw materials in our tires to 50% by 2030.
Fillers, mainly carbon black and silica, are one of the main raw material groups in a tire. The amount of fillers is around 28% of the tire, meaning that, in theory, it should be possible to increase the renewable raw material portion of the tire significantly by substituting fossil-based fillers with ones from renewable sources. There are several research programs ongoing, for instance researching materials based on forest industry side streams.
The use of renewable raw materials has not required us to change our production processes or had any significant effects on the energy consumption in production. However, renewable raw materials often increase the raw material costs of tires.
|Nokian Tyres' tire materials and their alternatives|
|Material||% of a tire (approx.)||Sources||Replacements and alternatives|
|Synthethic rubber||22||crude oil||• Needs active engagement from raw material producers.
• Recycled rubber crumbs
|Natural rubber||22||natural rubber||• Guayule as an alternative for natural rubber which is currently cultivated in South East Asia and some parts of Africa
• Recycled rubber crumbs
|Fillers||28||silica, carbon black||• Active research of different biobased fillers, for instance from forest industry side stream-based materials.
• Potential to use silica produced from rice husk in some products.
|Reinforcement materials||15||steel, textile||• Recycled steel is being used in our reinforcement materials.
• Researching the use of renewable or recycled sources for textiles.
|Softeners||5||low PAH oils||• Increase renwable or recycled oil and resin content in tires. Canola oil and tall oil already used, various vegetable oils researched.|
|Vulcanizers||6||• Reduction & elimination of harmful chemicals|
|Other chemicals||2||• Reduction & elimination of harmful chemicals|
FINDING altervatives FOR NATURAL RUBBER
Guayule-based natural rubber is one of the active initiatives that Nokian Tyres is working on. We are currently testing the suitability of different guayule varieties to be cultivated in central Spain, near our new testing center in Santa Cruz de la Zarza.
As guayule originates from the desert, it can survive in very dry and poor soil conditions. It is a plant that does not exploit areas of any other vegetation or food production, on the contrary, it makes use of wastelands. Nokian Tyres is collaborating with local farmers, universities, research institutes, and companies in Spain. Guayule is an opportunity not only for Nokian Tyres but also for the local agriculture and industry.
Currently, natural rubber that is used in tires comes from rubber trees (Hevea Brasiliensis), which are growing in areas around the equator. This results in long logistics chains for tire manufacturers located in the north, which is bad for the environment and also costly. If guayule succeeds as an alternative source for natural rubber, it will shorten the transporting distance and reduce the CO2 emissions.
Conservation of natural vegetation in tropical areas would be another environmental benefit. The substantial use of toxic pesticides on rubber plantations in Southeast Asia is a problem for the environment. Also, the South American leaf blight (Microcyclus Ulei) poses problems for the cultivation. The majority of the rubber rees in Asia are clones of varieties highly vulnerable to this disease.
Guayule, however, grows in dry areas, and no major plant diseases have thus far been identified as potential problems. It is also hypoallergenic, unlike the normal Hevea rubber. This is a relief for many people working in the rubber industry, logistics, and trade.
In Spain, studies have been continued on the Parthenium argentatum variety of the plant: what is the best way to maintain it, how to fertilize it and how to remove any weeds that may compete with the plant. The results have been promising, and in 2020, the researchers have developed a sustainable way of managing the plant where no synthetic biocides are needed.
Also, researchers have made promising experiments with cultivating the plants on poor soils in total absence of irrigation. Instead of planting ahead of the hottest season of the year, the planting had been carried out in the autumn to allow the survival of the plants. To affirm the promising results, the planting was carried out again in the next fall.
The researchers are also exploring the opportunities of plant waste as a part of a circular economy project, in which all the co-products of the plant are utilized.
In January 2021, there was unusual snowfall in the region due to the Filomena storm and the Madrid region recorded the heaviest snowfall in several decades. Despite the heavy snowfall, most of the plants survived and only some replanting was necessary. The exceptional weather phenomenon provided us with important knowledge on the survival of the plant in low temperatures and the effects it has on different varieties of the guayule plant.
MIDAS is a four-year EU financed project of marginal agricultural lands, climate-resilient and biodiversity-friendly industrial crops for innovative bio-based value chains. The project started in the end of 2022, aiming to develop innovative bio-based products following a bio refinery concept and the circular use of biomass. During the MIDAS project, our target is to explore further the use of guayule-based natural rubber in tires.